Lithium in Chilean drinking water may be causing hypothyroidism

High levels of lithium found in the drinking water of four hamlets in the Andes Mountains may be putting villagers at risk for hypothyroidism, according to a recently released report.

A study published in the journal Environmental Health Perspectives determined that the blood serum lithium levels of more than 200 women living in remote regions of Chile are dangerously high, most likely due to exposure to the element through groundwater.

Lithium, which is an alkali metal found in batteries and prescription mood stabilizers, has been used for centuries as a medical treatment for various ailments.

However, the use of lithium-based drugs is known to have several common side effects, one of which is impaired thyroid function, according to the National Patient Safety Agency. The same risk holds true for environmental exposure to lithium, which researchers from Sweden's Lund University said is a significant problem for the Andean villagers who participated in the new study.

The team stated that natural exposure to the element can cause thyroid disease, particularly since the women recruited for the study appear to have been ingesting water laced with lithium all their lives.

In the report, researchers describe using mass spectroscopy, a technique by which the concentrations of individual elements in a sample can be determined, in order to analyze participants' urine for lithium.

The group found that the Chilean women had abnormally high levels of the substance in their bodies, often up to a tenth of what an individual on lithium-based prescriptions would have.

Researchers theorized that the element leaches into the water supply via underground veins of ore.

An article published in the Journal of Psychopharmacology explains that the substance interferes with the production of thyroid hormone, particularly in women. The authors note that most studies put the incidence of lithium-related hypothyroidism at about 10 percent among those taking prescriptions containing the element.

The article also notes that impaired thyroid function caused by lithium can be permanent. The Swedish team concluded that drinking water should be tested for lithium in order to prevent individuals from unwittingly damaging their thyroid glands.